Apple (AAPL 0.20%) and Microsoft (MSFT 0.52%) are two of the biggest rivals in tech. And today, they're both spending heavily on artificial intelligence (AI) as their rivalry evolves into yet another chapter.They are among the most highly valued stocks in the world with market caps in excess of $3 trillion. Apple is ahead today, but which stock ends up more valuable in the next five or 10 years could ultimately depend on which business has the better AI strategy.In 2024, Apple's stock rose by 30% as it outp ...